Explainer

What is giant hogweed and what happens if you touch the 'dangerous' plant?

Giant hogweed has been found in a park in Leicestershire Credit: BPM

People are being urged to stay away from Britain's 'most dangerous' plant for their own safety as it took root in a park in Leicestershire.

Council bosses have issued advice after the giant hogweed plant was found at Market Bosworth Country Park.

The giant hogweed is one of a series of growths that have sprung up in the popular park for several weeks. This latest one has been seen growing close to paths in the area, with a warning now issued.

Able to grow up to 20 feet tall, giant hogweed poses a safety risk to the public as it has a dangerous side.

The hazards are so severe that the plant has been dubbed Britain’s "most dangerous" by experts as its touch can cause severe blisters and burns, while others could go blind depending on if they come into contact with certain areas of a giant hogweed.

Giant Hogweed is found all over the country

What is giant hogweed and is it poisonous?

Giant hogweed is not native to the UK and was first introduced into the country from Southern Russia and Georgia in the 19th Century.

A towering plant that can reach up to three meters (10 feet) in height and it is similar in its appearance to cow parsley, one of the reasons that it is a danger to those who are unaware of the risks associated with touching hogweed.

It is part of the Apiaceae family and commonly found in gardens and allotments which are next to infested woodland or common land during spring to autumn.

It can look attractive but the chemicals in the sap can cause photodermatitis or photosensitivity, where the skin becomes sensitive to sunlight and may suffer blistering.

It poses a serious risk to people who are unaware of its potential for harm.

Giant Hogweed.

What's the difference between hogweed and giant hogweed?

Hogweed is a common native plant in the UK – unlike giant hogweed – and can be found in abundance in hedgerows.

The Wildlife Trusts describes it as a member of the "carrot family" - displaying large, umbrella-like clusters of creamy-white flowers between May and August that are attractive to insects, although it can flower all year round.

In the New Journal of Botany, published in 2013, giant hogweed was described as "a threat to public health."

The Royal Horticultural Society explains that the primary danger posed by giant hogweed to humans is the plant’s sap, which if it gets onto the skin and the skin is exposed to sunlight, can cause burns and blistering.

The Market Bosworth plant may not have reached the heady heights of 20 feet, but it is no less perilous than one of the bigger variants.

Found close to paths used by the public, people are now being urged to keep clear of the Market Bosworth plant in a bid to avoid risking serious injury.

What effects does the giant hogweed have?

Hogweed burn Credit: MEN Syndication

These risks mainly centre on the giant hogweed’s hairy sap which contains toxic chemical compounds that can cause major irritation and blistering to people’s skin.

Longer-term consequences of touching the plant could also lead to potential disfiguration or long-lasting purple blotches on the skin - a problem that could last months or years.

If people come into contact with the sap, the risks are even greater, with people potentially going blind if the sap makes contact with the eye.

Where has the giant hogweed plant been found in the Midlands?

Last week, a new map revealed that the plant is in several parts of Leicestershire, with giant hogweed plants found near Coalville and East Midlands Airport.

Experts advise anyone who sees the plant to stay away from it for their own safety.

What should you do if you see giant hogweed?

Leicestershire County Council, which oversees Market Bosworth Country Park, have called on anyone who spots the dangerous plant to let them know as soon as possible."Our park rangers are aware that giant hogweed has been identified at Market Bosworth Country Park. It is potentially harmful and we already treated and removed a number of plants last month,” said a spokesman."When if we become aware of new ones they too are dealt with as swiftly as possible. We believe the source of the weed is land near to the park and we have been in contact with its owner to encourage them to treat it.

"Anyone who spots giant hogweed in the park is urged to stay well clear of it."

Anyone with sightings of giant hogweed should call 0116 3055000 or email countryparks@leics.gov.uk. People should also supply a photo and location alongside their reports.

How can you get rid of it safely?:

  • There are two ways to get rid of hogweed; chemical means or non-chemical means, such as digging it out the roots out

  • The Royal Horticultural Society says you must always wear gloves, cover your arms and legs and wear a face mark when removing it

  • If the hogweed is in a garden it can be removed by simply pulling up young plants immediately in moist soil, using measures outlined above

  • For larger plants you can loosen the roots with a fork first

  • If you choose to use weedkiller, choose one that is appropriate for the purpose by reading the label carefully

  • Systemic weedkillers based on glyphosate are usually the best choice as these kill the roots also

  • Wash any skin that may come into contact with the plant at once and make sure you dispose of any plant debris, clothing or tools that have come into contact with it, as these can be hazardous too

Giant hogweed is a controlled waste so it can only be disposed of in licensed landfill sites with the required documentation.

You can safely dispose of any plant material by composting or burning.